Blade holder with sliding blade assembly



oct. 31j, 1967 w. A. Roems BLADE HOLDER WITH SLIDING BLADE ASSEMBLY Filed Jan. 12, 1966 LL.; LL L L .L LL LL L l, L/ L.. L L LL L L L .L L L! L L ,L o LL lv,/LLxLLLfML LL/LLL LLL M., L 4/ M LL L x.o. a

United States Patent Otice 3,349,487 BLADE HOLDER WITH SLIDING BLADE ASSEMBLY Walter A. Robins, 3127 N. Vane Ave., El Monte, Calif. 91733 Filed Jan. 12, 1966, Ser. No. 520,130 3 Claims. (Cl. 30-33S) This invention relates in general to knife structures having shieldable blade edges, and more specifically to a holder for a replaceable, disposable blade.

There are numerous devices provided for holding razor blades as disposable knife edges, some of which are speciiically designed for specific purposes. Such disposable and replaceable blades serve widely-divergent purposes. One such blade-holding device serves as a wood plane, whereas a popular type holder makes an excellent opening device for paper cartons in the food supermarkets.

It is an object of this invention to provide a replaceable lblade structure wherein the cutting edge of the blade may be completely shrouded within a holding collet for safe storage with other objects or upon the person of the user.

A still further object of this invention is to provide a collet-held, replaceable blade and to make the blade extendable to any degree up to a major portion of the blade, according to the need the blade is to serve.

A still further object of the invention is to make available a holder for a popular injector-type razor blade -in order to produce a compact-size knife device substantially comparable in size to a fountain pen.

In accordance with these and other objects which will become apparent hereinafter, the best mode contemplated for the present invention is disclosed in the accompanyin g drawing wherein:

FIGURE 1 is a plan view of the preferred embodiment of this invention;

FIGURE 2 is a View of one-half of the collet holder element;

FIGURE 3 is a view of the opposite half of the collet holder element; and

FIGURE 4 is a view of the assembled collet member, with the cam drive collar in cross section, and the handle member in phantom outline.

The drawing illustrates a preferred pocket type of knife made according to this invention, which may be used when sewing and stored in the sewing basket, used and stored in the workshop, carried on the person of the user, or in many other similar uses and storage locations. The preferred embodiment Iis easy to carry or store, being preferably comparable in size to a conventional fountain pen.

In the FIGURE 1, a collet sheath and handle 12 are shown assembled in the condition of ordinary use, with a blade 13 extended a short -distance out of the collet.

In the FIGURES 2 and 3, two half members 14 and 16 are shown in position to reveal the internal bladeholding surfaces. These two half members, when united, constitute the full collet sheath 10 of FIGURES 1 and 4. In FIGURE 2, half member 14 and in FIGURE 3, half member 16, show the mating relationship. Member 14 has a longitudinally-extending, blade-receiving guide trough 18 in which the blade 13 may slide and be held to a longitudinal path aligned with the longitudinal axis of the sheath 10.

Half member 16, on the other hand, as shown best in FIGURE 3, has a ridge 20` which corresponds to the width of the trough 18, and would substantially ll the trough when the two members are mated, but for the presence of the blade 13. Hence, a tight gripping of 3,349,487 Patented Oct. 31, 1967 the two half members 14 and 16 will grip the blade 13.

Half members 14 and 16 may be made of a wide variety of material, but preferably a modern plastic material should be selected because of its gripping nature upon a steel blade, Whereas a smooth metal collet will have less coefficient of friction with respect to the steel blade. Nevertheless, a metal half member properly conditioned to grip blade 13 would sutlice.

One of the desirable features of this invention is the ability of the collet sheath 10 to hold the blade 13 extending from the end of lthe collet with a major portion of the blade 13 exposed for use, and yet properly supported for good cutting action. Nevertheless, the blade may be retracted to expose only a very small corner of the blade whenever delicate carving or controlled depth of cut is desired. A cutting edge 24 of the blade 13 is thus available to the degree desired.

In order to prevent the blade 13 from becoming lost in the collet 10, and also to assure the proper alignment of the half members 14 and 16, one of the members, being the member 14 in the illustration, is provided with a hole 26 and the other with a pin 28. The half member 16 is shown with the pin 28 in FIGURE 3. This pin 28 then provides a maximum retraction abutment and prevents the blade being retracted too deeply within lthe collet.

The combined collet 10 composed of the two half members 14 and 16, presents a cylindrical exterior stem configuration 30 and a head portion 32. The head 32 has a forwardly-sloping annular cam surface 34 which ends in an abrupt shoulder 36 at the union with the cylindrical stem 30.

The handle 12 has an axial bore 38 opening from the forward end thereof, and the stem 30 ts with a reasonably close t into the bore 38. In the bore, stem 30 is held stable and given support by the handle, but is free to open to a degree suicient to allow the blade to become loose in the collet.

A collar 40 serves the purpose of holding the collet sheath in the bore of the handle, and also as a cam drive agent to cause the half members 14 and 1.6 to clamp down upon the blade. Collar 40 has a tapered forward v end which serves as a cam drive. The internal surface of the end 42 is the active surface and the exterior surface can be of any convenient configuration.

The collar 40 has a threaded body 44 which is threadably engaged upon handle end threa-ds 46 which surround the forward end of the handle 12 at the bore 38. Thus, the collar will serve as means to press radially inwardly upon the cam shoulder 34 for clamping the members 14 and 16 upon the blade 13 in a blade-holding grip.

In order to provide convenience, making unnecessary the loosening and shaking of the blade from the holder after it is completely sheathed, the head 32 is notched by a recess 48, thus producing a resultant blunt nose 50. The nose 50 is spaced from the location of the pin 28 such that when the blade 13 is against the pin 28 as a backstop, the opposite end of the blade is merely within the confines of the nose 50. Thus, a corner of the blade projects out of the holder, as seen best in the FIGURE 4, and may be grasped by the lingers to draw the blade out to the desired position of use, prior to tightening the collar 40 in order to hold the blade at that selected position.

Whereas the present invention ha-s been shown and described herein in what is conceived to be the best mode contemplated it is recognized that departures may be made therefrom within the scope of the invention which is, therefore, not to be limited to the details disclosed herein, but is to be afforded the full scope of the invention as hereinafter claimed.

What is claimed is:

1. A cutting blade instrument, comprising in combination:

a collect sheath composed of a pair of elongated members jointly defining an external cam shoulder and an internal guiding and holding raceway,

said raceway comprising a blade-receiving guide trough in one of said members and a ridge on the other of said members closely fitting into said trough;

a cutting blade proportioned to reside Within said raceway, said blade being longitudinally slideable in said raceway between a position fully retracted within said sheath -to a fully removed condition;

each said member having an end recessed surface jointly defining a projection of said sheath along only one edge of said trough, whereby one corner of said blade may be exposed for providing a linger grip to grasp said blade with all of the cutting blade edge retracted into said sheath; and

means to press radially inward upon said cam shoulder for clamping said members upon said blade in a blade-holding grip.

2. A cutting blade instrument, comprising in combination:

a collet sheath, said sheath composed of a plurality of elongated members jointly dening an external cam shoulder and an internal guiding and holding raceway;

a cutting blade proportioned to reside Within said raceway, said blade Ibeing longitudinally slideable in said raceway between a position fully retracted within said sheath to a fully removed condition;

means to press radially inwardly upon said cam shoulder for clamping said members upon said blade in a blade-holding grip, said -means comprising:

a handle having an end bore;

said collet sheath members jointly dening a stem portion slideably receivable in said bore, a shoulder larger than said bore providing an abutment, a cam surface on one side of said shoulder opposite said stem portion, and a pin on one member and a socket on another member providing guide interconnection and a limit stop for a blade in -said trough; and a collar threadably engaged on the end of said handle, a drive cam surface carried by said collar, said drive 5 surface retractable against said cam surface by threadable advancement of said collar to produce a radially inward force upon said members for clamping said members upon said blade in a blade-holding grip.

3. A cutting blade instrument, comprising in combination:

a collet sheath,

said sheath composed of a pair of elongated members jointly defining an external cam shoulder and an internal guiding and holding raceway;

said raceway being comprised of a blade-receiving guide trough in one of said members, and means on the other of said members for holding a cutting blade in said guide trough;

a cutting blade proportioned to reside .within said raceway, said blade being longitudinally slideable in said raceway between a position fully retracted within said sheath to a fully removed condition;

each said member having an end recessed surface jointly defining a projection of said sheath along only one edge of said trough, whereby one corner of said blade may be exposed for providing a linger grip to grasp said blade, with all of the cutting blade edge retracted into said sheath; and

means to press radially inwardly upon said cam shoulder for clamping said members on said blade in a blade-holding grip.

References Cited UNITED STATES PATENTS 9/1949 Urban et al 279-56 8/1951 Benham 279--56 X 

3. A CUTTING BLADE INSTRUMENT, COMPRISING IN COMBINATION: A COLLET SHEATH, SAID SHEATH COMPOSED OF A PAIR OF ELONGATED MEMBERS JOINTLY DEFINING AN EXTERNAL CAM SHOULDER AND AN INTERNAL GUIDING AND HOLDING RACEWAY; SAID RACEWAY BEING COMPRISED OF A BLADE-RECEIVING GUIDE TROUGH IN ONE OF SAID MEMBERS, AND MEANS ON THE OTHER OF SAID MEMBERS FOR HOLDING A CUTTING BLADE IN SAID GUIDE TROUGH; A CUTTING BLADE PROPORTIONED TO RESIDE WITHIN SAID RACEWAY, SAID BLADE BEING LONGITUDINALLY SLIDEABLE IN SAID RACEWAY BETWEEN A POSITION FULLY RETRACTED WITHIN SAID SHEATH TO A FULLY REMOVED CONDITION; EACH SAID MEMBER HAVING AN END RECESSED SURFACE JOINTLY DEFINING A PROJECTION OF SAID SHEATH ALONG ONLY ONE EDGE OF SAID TROUGH, WHEREBY ONE CORNER OF SAID BLADE MAY BE EXPOSED FOR PROVIDING A FINGER GRIP TO GRASP SAID BLADE, WITH ALL OF THE CUTTING BLADE EDGE RETRACTED INTO SAID SHEATH; AND MEANS TO PRESS RADIALLY INWARDLY UPON SAID CAM SHOULDER FOR CLAMPING SAID MEMBERS ON SAID BLADE IN A BLADE-HOLDING GRIP. 